Process of metal cutting, welding, or the like



March 16 1926. 1,577,171

R. H. BROWNLEE ET Al.

PROCESS OF METAL CUTTING, WELDING, OR THE LIKE Original Filed June` 1,1.915` 2 Sheets-Shee'll 1 March 1 1926. 1,577,171

R. H. BROWNLEE ET AL -v y PROCESS OF METAL CU'FI'IPII WELDING.y OR THELIKE Original Filed June l, 1915 2 Sheets-Sheet 2 7/2 12e/ana PatentedMar. 16, 1926.

gUNITED STATES rPATENT OFFICE.

ROY H, BROWNLEE AND ROY H. UIILINGER, OF PITTSBURGH, PENNSYLVANIA, AS-SIGNORS, BY MESNE ASSIGNMENTS, TO CARRO-OXYGEN COMPANY, OF PITTS-BUIEtCirl'd'., PENNSYLVANIA, A CORPORATION 0F DELAWARE.

PROCESS OF METAL CUTTING, WELDING, R THE LIKE.

Original application :tiled June 1, 1915,

To (/Z/ gliom. 'it may concern:

Be it known that we, ROY H. BnowNLnn and Ror H. UHLINcnn, citizens ofthe liiited States, residing at`223 Fourth Avenne, Pittsburgh, in thecounty of Allegheny and State of Pennsylvania, haveinvented certain newand useful Improvements inI Processes of Metal Cuttiug,-\Velding, or thelike, of which the following is a specification.

(hir invention relates to an improvement ir. a process of metal cutting,welding or the like using a gas containing hydrogen and carboncompounds, and this application is :i division of application Serial No.31,441, filed Julie 1, 1915.

The gas used is especially suitable with oxygen as a combustion jet, forlead burning, brazing of brass and aluminum, the cutting and welding ofiron and steel, and like operations requiring a high combustion.However, it is not restricted in its usefulness to these particularpurposes, but may be applied in any case where Aa highly combustiblegaseous heating fuel is used. The objects of the invention are toproduce an economical, efficient, safe and practical process or flamevfor lead burning, brazing and the welding and cut-ting of iron and steelor other metals.

A gas especially suitable for the above purposes, consists of materialsassociated in approximately the following'- proportions: hydrogeneighty-seven (87%) per cent, hy drocarbon nine (9%) .per cent, andcarbon monoxide four (4%) per cent. The constituents of gas may vary,however, between certain limits. For exam le, the percentage of hydrogenand' hy rocarbon in the case or parafiin hydrocarbons may vary dependingupon tlie nature o'f the hydrocarbon used and the work for which thecom-A position is required.

Also, the proportion of carbon monoxide may 'vary between certain Whenethylene 'and acetylene hydrocarbons are "used, their proportion-may begreatly increased over the amount of paralin hydrocarbons. This will bereadily understood when it is explained that for-uses to which we desireto putthis gas, it is essential that the gas employed must have a veryhigh rate to be gas-tight.

Serial No. 31,441. Divided and this application filed August 13,

Serial No. 49,958.

of combustion. For example, methane, having an extremely low rate ofcombustion, can be employed in amounts up to twelve or fifteen (12(/0'or15%) per cent, whereas when hydrocarbons of the ethylene and acetyleneseries are employed considerably larger proportions may be used owing totheir higher rate of combustion.

This gas may be prepared in a single oper- 2 is constructed towithstandthe pressure of several atmospheres, preferably provided withhighly refractive linings 3 of suitable fire brick, and near the bottomis a supporting checker-work 4 of similar material.

A filling of irregular pieces of refractory lnaterial 5 is containedwithin the body of the generator, above the supporting checkerwork, orthe entire inner part of the generator may be built up of checker-workof suitable refractory brick. f'

At the top of the generator is a stack 6 provided with a suitable dampervalve 7 for closing the stack and Inlet pipes 8 for supplyinghydrocarbon,

such as natural gas, are introduced through the upper portion of thegenerator. A damper controlled air conduit 10 having a damper or 'valve11 and a gas pipe 12 having a controlling valve 13, are introduced tochamber 9 below the 'checker-work or refrac? to material 5 for heatingthe generator an its contents. Y

Leading outwardly from the base of the generator 2, at any suitablelocation, is a conduit 14 provided with an opening and closing valve ordamper 15 for controlling the circulation, beyond which the conduitgenerator so as is connected with the tubular conveyor 16. Said conveyorextends through a cooling bath 1T of water within a surroundingenclosing tank or casing 18, provided with a supply connection 19 and anoverflow 20.

'lhe other end of the conveying conduit 1G leads to a receiving hopper21, provided with an outlet controlling valve 22 at its lower portionfor removal of carbon. At the upper end of this hopper is a screen .boxportion, between which and the lower portion of the hopper preferablyextends a sloping partition or shield 22.

The conduit 16 is provided with a rotatable screw conveyor 26, actuatedby shaft 2T driven by any suitable gearing, as a pulley or sprocketwheel 28, whereby to propel the precipitated carbon fthrough theconduit. llhe upper screen box'portion Aof the hopper is provided withfine screens 30 of cloth or other filtering medium of a suitable natureto filter out the carbon carried along with the These screens arepreferablyv mounted adjustably within the casing, as by hinged mountings23, and are adapted to be raised to horizontal operative position,shown, or to be lowered, as indicated in dotted lines, whereby, by asuitable lever mech anism on the outside of the easing, any collectedcarbon may be. dropped int-o the hopper below. The outlet at the upperportion of the easing is provided with a suitable safety valve 24: and apressure indicating gauge Beyond the screens is a conduit 31 leading toa water seal vessel 32, in which the terminal of the conduit issubmerged and conduit. 33 leads from the upper portion of water sealvessel 32 to a scrubber 34 of any suitable construction, provided withporous material and a. water spray 3G, whereby the gases are furthercooled and washed.

An additional scrubber 37 may also he provided, connected with theprimary scruh ber 231 by a circulation pipe 38. into which additionalscrubber a spray pipe 39 of lime water or other alkaline material may beiutroduccd, by which impurities in the gas are removed, such as tracesof sulfur com )ounds in the gas or other hydrocarbon used. The gaspasses off by outlet pipe 40 to any sultnble collecting or storage tank.

At any suitable point beyond the carbon separator or screen box 2l isthe automatically regulated pressure relief valve 46 for holding thedesired pressure iu the generator and carbon separator. Such valve is`preferably situated between the carbon separator and the water seal 32,but may also be inserted in the line beyond the. scrubber-s, ifpreferred, for the same purpose.

It will also be understood that the pres sure in the generator 2 may beregulated by valve 15 or valve 46, or lower pressures, as

a few ounces above atmospheric pressure may be regulated by the depth ofthe end of the conduit 31 in the water seal 32.

The operation of making the gas, utiliz ing the above describedapparatus, having reference to the apparatus of Fig. 1, is as follows:

lVith the valve T in stack G opened, and valve 15 to the carbonprecipitating conduit 16 closed, gas (natural gas, coal gas, oil vaporor other hydrocarbon, preferably as a gas, liquid or volatilizablesolid) is admitted through pipe 12 with a suitable amount of air byconduit 10 to chamber 9 below the checker-work for the completecombustion of fuel.

The products of combustion pass upwardly through the interior ofgenerator 2 and its refractory contents 5, the operation bef ingcontinued until the generator and its contents are heated to a very highteniperature, that is, above the temperatureat which part of thehydrocarbons to be used in the formation of this composition are decomposed.

Then a suitable temperature has thus been reached, say 1200 degrees C.or higher, the air supply 10 by valve 11 and then the gas supply 12 byvalve 13 is shut olf', the stack valve 7 is closed, and valve 15 to thecarbon precipitator is opened. Then the valves in the pipe or pipes 8 atthe top of the generator are opened, and gas or other hydrocarbon, withor without a regulated small amount of water vapor, is introduced at thetop of the generator, and if used, the small amount of water vaporrequired being` determined by the amount of carbon monoxide desired inthe gas. The small amount of carbon monoxide desirably present in thegas, even though no water vapor is directly added, is derived from theslight traces of moisture usually present in the hydrocarbon used. andalso from the slight reduction of oxides in the refractory material.

The hydrocarbon and moisture passing downwardly in contact with the veryhighly heated surfaces of refractory material 5, and in the absence. ofair. is decomposed to form the gas and carbon black.

These elements pass out ardly from the base of the generator throughconduit 14. entering the conveying conduit 16, heilig carriedtherethrough by conveyor 2G through the cooling water bath 17,effect-ing precipitation of the carbon, which is discharged by theconveyor into hopper 2l, or washed away by 'atei' (Fig. 3).

The gas passing`through the automatic pressure regulating valve 46, thewater seal tank 32, andthe washing tanks 31 and 87, and finally to aholder, is t-hus completely cleansed of any suspended impurities.

The Operation eben? described is cfmtinued until the temperature 1n thegenerator Q- has been reduced to a. degree below which a satisfactoryreaction does not occur,

Awhereupon the supply of, hydrocarbon gas through pipe 8 shut ottl atthe top of the generator, after pressure in the furnace is reduced toatmosl'ihericpressure b v opening the 'regulating valve 46.

Valve 15 to the precipitator conduit 1G is then closed, stack valve 7 isopened, and gas and air are again admitted from connections 12 and l()for additional combustion and heating of the refractory contents of thegenerator, preparatory to a repetition of the operation just described.

In case a liquid or volatilizable solid is used as a fuel at the base ofthe generator, it may be sprayed or blown into theV combustion chamber 9with an air blast. lVhen y the same kind of hydrocarbon is used at thetop of the generator, as in Fig. 2, instead of gas, for the making ofthis composition and carbon black, it may also be sprayed in underpressure, or atomized by aid of compressed hydrogen without air, so thatonly minute particles of the will strike the hot checker-work, by usinga suitable atomizer.

Otherwise the entire checker-work would soon be clogged with carbon,whereas, when either a gas or very fine spray is used, the finelydivided carbon is carried down with the gas.

In case a higher' proportion of hydrocarbon is desired the natural gasemployed or other hydrocarbon used lis passed through the generator morerapidly than when only a small amount of hydrocarbon is desired, or thegenerator may be run at a low tempera-ture, so that only a part of thehydrocarbon is decomposed to form hydrogen and carbon black, and theremainder .is carried through the generator, mixed with the hydrogen asa fixed gaseous hydrocarbon, which remains mixed and may be employed inthe usual operations previously described.

Fig. '2.shows a modified arrangement of the generator 2, whereby theproducts of combustion for heating the refractory material 5a leaddownwardly from the top to a suitableoutlet 6, gas being furnished atthe top by pipe 12a having a valve 13, and air by pipe 1,0*l having avalve 11".

The gas to be decomposed in such case eut-ers through the base of thegenera-tor by pipe 8, passing upwardly through the checker-work orrefractory material 5, and outwardly at the top through conduit 14.

Conduit 14; is likewise -provided 'with a controlling valve 15a, and aconduit 16a extends vertically down within and through a body -of water17a in casing 1Sa provided with a supply connection 19a and an overow20a.

The lower end Aof the conduit 143a opens into a hopper 21a of the sameconstruction as above described, adapted to collect the" .is carriedover into the conveying conduit,

and leaves more in the checker-Work, where it is burned during thesucceeding heating periods.

In Fig. 3, we show in detail a modified arrangement in which tliegasfrom the generator 2 or 2 is conducted by conduits 11th. and 1G" to awater seal vessel'BQ", into which the carbon is discharged, the gaspassing off by conduit to a holder or other apparatus. v

In such case an overflow pipe 461 leads o'-, at the desired water level,having a gooseneck section 471 providing a water seal, and lading to anylsuitable point of discharge.

A spray pipe 481 is introduced at the upper end of conduit 16", asshown, whereby to furnish ample water supply and assistin precipitationof the carbon.

If desired, conduit 1Gb may be surrounded by a water jacket similar tojacket 18a,

whereby to protect conduit 161 and cool the y gas and carbon incirculation. l

The gas may be made as explained above so as to produce a gas containingonly a verysmall proportion of hydrocarbon and the hydrocarbons of theethylene acetylene or paraffin series may be added from a separatesource, of these different constituents may of course be added to purehydrogen, as indicated above. Y I

The gas is used in the process of metal cutting or welding, whichprocess consists in mixing with oxygen the gas, and applying the flameof combustion of the voxygen-` gas mixture to the metal. y

There are a number of advantages in the use ot' a large proportionofhydrogen in the mixture, with small proportions of hydrocarbon andcarbon monoxide. Thus, 1n using a large proportion of hydrogen(substantially 7 5% or overof the mixture), this in the presence ofoxygen, and just sufficient carbon monoxide is used' according to thework to be done to avoid oxidation ot' the metal Worked 0n in case ofWelding. The amount of hydrocarbon is small in proportion and percentageof the gas according to the grade of hydrocarbon used, so as not to slowup in effect the high rate o'f combustion. Thus, the amount et'hydrocarbon will be substantially 5% or over of the mixture and will*ary with ditlerent grades ot` hydrocarbons, and it is important that,as described hercinbefore, the proportion of the particular hydrocarbonbe regulated according to the grade ot the hydrocarbon and the largeproportion of hydrogen, so that the desired results are obtained. lt anextreme ly small or negligible amount ot' hydrocarbon is used, then thedesired results are not present, just the same as it pure hydrogen wereused, Whereas it a larger amount ot hydro'carhon is used as in coal gasor natural gas, this slows up the rate ot' combustion, so that the gasis not etl'ective for metal cut ting. Welding and other heatingpurposes. rl'liere is, therefore, a relation established between thesmall proportion of hydrocar-l bon according to the grade thereof, andthe large proportion of hydrogen. The use ot' carbon monoxide is ofadvantage, when it is used in a small amount (less than 10% of themixture), the amount being sufficient according to the work to be donefor prerenting oxidation of the metal, and being small in proportion tothe hydrogen and percentage of the gas, soas not to materially cut downthe heat produced. Gtherwise, the advantages sought for are lost. Thehydrogen, hydrocarbon and carbon monoxide can be mixed, but the processhas its advantage due to the homogeneous mixture of partially decomposedand partially nondecomposed hydrocarbon of suitable grade, thedecomposed hydrocarbon being freed of its carbon. Thus, the hydrogen andsmall percentage ot hydrocarbon are obtained from a single source andare mixed during partial decomposition, and it has been found that thismixture when freed of carbon, is very successful in practical use, andmay be preferred, in many instances, to mixing pure hydrogen with ahydrocarbon and carbon monoxide.

Having thus described the invention, what is claimed as new is l. Theprocess of metal cuttingor Welding consisting in mixing with oxygen agas including substantially or over of hydrogen and substantially 5% orover of hydro-carbon, and applying the flame of coni bastion of theoxygen-gas mixture to the metal.

2. The process of metal cutting or Weld ing consisting in mixing withoxygen a gas including substantially 75% or over of hydrogen,substantially 5% or over of hydrocarbon and not over 10% of carbonmonoxide, and applying the flame of combustion ot' the oxygen-gasmixture to the metal.

3. The process of metal cutting or Welding consisting in mixing withoxygen a gas the major portion of which consists ot hydrogen with aminor proportion ot' hydrocarbon, and applying the llame ot combustionof the oxygeirgas mixture to the metal.

f1. A metal `cutting or Welding llame co1n-v prising the mixture withoxygen of a including substantially 75% or over of hydrogen andsubstantially 5% or over of hydro-carbon.

5. A metal cutting or Welding flame coniprising the mixture With oxygenof a gas including substantially 75% or over of hydrogen, substantially5% or over of hydrocarbon and not over 10% of carbon monox ide.

G. A metal cutting or Welding llame coinprising the mixture with oxygenof a gas the major portion of which consists of hyn drogen with a minorproportion of hydrocarbon.4

In testimony whereof we hereunto atlix our signatures.

ROY H. BROVNLEE. ROY H. UHLINGER.

